Key left on - won't start with jump

[montana_norsky]

First ride yesterday after a long Montana winter (and it's not over yet) and left the key on when I went into the grocery store. Battery is, of course, dead. I came back later and jumped the bike with my little battery pack. This is usually big enough to jump it but all I got was the same fast ticking sound as I got without the jumper battery. Before I head back again with my pickup does anyone know if there is anything else, besides a simple dead battery, that I need to know about. No fail-safe circuit, switch, doohickey that needs to be reset when the key is left on?

Thanks

 

[wnyfjr]

None that I know of, but I've never had to jump start mine. Last time it went limp I was able to get a battery tender on it and all ended up well. Obviously not as easy in this case. Hope you get it running!

 

[Bounce]

Just don't jump it from a running car. Have the car's charging system off before connecting to the bike to avoid its higher amps and the possibility of frying something on the bike.

Maybe, after the long sleep, the battery could use a deep charge (like the battery tender comment above). The age of the battery should help gauge if it might survive a deep discharge.

 

[Geezer]

I was able to push start mine one time. As long as there is enough power to run the fuel pump and make a spark it might start with a push.

Another possibility is a loose battery cable at the battery.

If that doesn't help then leave the jumper on for a while to transfer some energy to the battery, then try to start it.

 

[JamesW]

Whatever happens I would get a new battery, I never trust one that has been completely discharged.

 

[Bill Lumberg]

Compared to cars and car batteries, motorcycle batteries are strictly sketchistan. I had a bike that would sound the horn softly when the ignition was on and the bike wasn't running. Never could figure it out. Replaced the battery for some unrelated reason, and it stopped (the anomaly) permanently. While I usually get fairly long life out of bike batteries, my 2014 FJR started hesitating to start, despite the bike being pretty much ridden daily. A new battery fixed the problem, though the battery had never been drained, never been left sitting long enough to discharge.

 

[Guitardave]

Right on. Jumping with a car battery, (with the Car NOT running) should be enough to get you home.

My friend and I Frankenstein a car battery in parallel all the time when we work on

junk & non running bikes until we get them going.

It saves us from killing the bike's battery with multiple starts,

and it's also useful for when the bike has no battery at all.

We just have a car battery sitting there on the lift with long cables already made up.

We never hurt anything or fried anything.

Once again, to be clear, there is nothing hooked to the car battery,

and if it was in a car, the car should be turned off / not running.

 

[RossKean]

Sometimes you have to leave the donor battery connected for a few minutes after getting the bike started. If the voltage is too low to run the ECU and injectors, it will die immediately.

 

[jpriest]

12Volts is 12volts. IF your bike is a 12V system (which most these days are) you can jump start your bike with a 12 volt battery that is capable of 1100 cranking amps. Your bike is only going to draw what it needs. Same principle as a light bulb. You can replace a 100w bulb with a 60w bulb. Then it only draws 60w. You aren't "pushing" 100w through a 60w bulb. The bulb is the load, it uses the amps it is designed to use and you are not pushing any more into it than that. In our case the bike electrical system is the load and it is only going to draw what it is demanding.

If you have an electrical fault such as a short circuit, then your load WILL be larger and regardless of whether the car is running or not, it's battery is capable of several hundred amps and you will have a spectacular light show no matter what battery you are using to jump start. THAT is a whole different issue from a simple dead battery.

So if you fry an ECU, ECM or other component when you jump start, it is not because the car was running or you used too big a battery. It was going to fry anyway because there was some other fault already. (Or you hooked up the cables improperly and just don't want to admit it

)

To the OP: If your battery is completely dead and you use a similar or smaller battery to jump start it, the dead battery may be using all available power from your donor battery to try charging itself and not enough is left over to actually start the bike. In this case you could disconnect the negative lead from the bike battery then connect your jumper battery to the positive and negative lead. It should jump it then. But to keep it running you will probably have to connect the negative lead back to the bike's battery before you disconnect your jumper.

 

[wfooshee]

Nope. Do NOT run the bike, even for a few seconds, with the battery disconnected! The charging system needs that load!

Similarly, the car not running advice is not to protect the battery, or the ECU, or anything else, it's to protect your charging system, and rectifier/regulator components. When the bike starts and a running car is connected, all kinds of things are present that those systems cannot deal with. When it's just the car's battery, that's bad enough, but the car's charging system fighting against the bike's, guess which one wins?

 

[Enn]

Well, actually jumpstarting with a running car can potentially be harmful for your car electrics itself. Like burn down some diods on your car's alternator. Voltage drop!

 

[TownsendsFJR1300]

Plus one re jumping from a NON RUNNING car/truck, ...

Then fully charge YOUR battery and get it LOAD TESTED. It'll likely fail at this point.

 

[Bounce]

Standard car and bike batteries aren't designed to deep discharge like boat batteries.